Intervention times series analysis of pertussis vaccination in England and Wales.

We use the ARIMA model with intervention in order to analyse the epidemiological situation of whooping-cough in England and Wales for the period of 1940-1990. The ARIMA modelling of this illness contains intervention variables, such as the introduction of widespread vaccination in 1957 and the fall in the level of vaccination down to 30% in 1978. The results of this analysis confirm the role of the intervention variables on the evolution of the morbidity due to whooping-cough, by quantifying their impact on the level of the morbidity, as well as the delay needed before they have an influence on the increase of recorded cases of whooping-cough.